diff --git a/src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp b/src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp index 3222a0262ebfd5dabfac8f74c69cff4fd25a1e9f..caf642d0847b92e401a1feee7f934f6239cdd889 100644 --- a/src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp +++ b/src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp @@ -1048,6 +1048,7 @@ void ShenandoahBarrierC2Support::fix_ctrl(Node* barrier, Node* region, const Mem Node* u = ctrl->fast_out(i); if (u->_idx < last && u != barrier && + !u->depends_only_on_test() && // preserve dependency on test !uses_to_ignore.member(u) && (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) && (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) { diff --git a/test/hotspot/jtreg/gc/shenandoah/compiler/TestLoadBypassesNullCheck.java b/test/hotspot/jtreg/gc/shenandoah/compiler/TestLoadBypassesNullCheck.java new file mode 100644 index 0000000000000000000000000000000000000000..2feea3308e48a9eac0ba2cf14f20a51e318ee478 --- /dev/null +++ b/test/hotspot/jtreg/gc/shenandoah/compiler/TestLoadBypassesNullCheck.java @@ -0,0 +1,69 @@ +/* + * Copyright (c) 2024, Red Hat, Inc. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/** + * @test + * @bug 8342496 + * @summary C2/Shenandoah: SEGV in compiled code when running jcstress + * @requires vm.flavor == "server" + * @requires vm.gc.Shenandoah + * + * @run main/othervm -XX:-TieredCompilation -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -XX:+StressGCM + * -XX:+StressLCM -XX:+UseShenandoahGC -XX:LoopMaxUnroll=0 -XX:StressSeed=270847015 TestLoadBypassesNullCheck + * @run main/othervm -XX:-TieredCompilation -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -XX:+StressGCM + * -XX:+StressLCM -XX:+UseShenandoahGC -XX:LoopMaxUnroll=0 TestLoadBypassesNullCheck + * + */ + +public class TestLoadBypassesNullCheck { + private static A fieldA = new A(); + private static Object fieldO = new Object(); + private static volatile int volatileField; + + public static void main(String[] args) { + for (int i = 0; i < 20_000; i++) { + test1(); + } + fieldA = null; + try { + test1(); + } catch (NullPointerException npe) { + } + } + + private static boolean test1() { + for (int i = 0; i < 1000; i++) { + volatileField = 42; + A a = fieldA; + Object o = a.fieldO; + if (o == fieldO) { + return true; + } + } + return false; + } + + private static class A { + public Object fieldO; + } +}